Chapter 7

Weather

short term state of the atmosphere: temperature precipitation humidity, wind, cloud cover

Temperate grassland climate

(e.g. short-grass and tall-grass prairies):Temperate grassland winters can be very cold, summers are hot and dry, and annual precipitation is fairly sparse and falls unevenly through the year.

Decomposers

(mostly bacteria), which break down organic compounds in the dead bodies and wastes of aquatic organisms.

Major ABIOTIC factors influencing energy distribution and air circulation

1. Sun - Uneven heating of Earth's surface- equator gets more direct sun 2. Earth's rotation - equator rotates faster than poles- deflects air movement 3. Physical properties of air, water, and land- leads to 6 major convection cells 4. Energy often transferred by convection

About ___ of the earths surface is covered with salty ocean water

71%

5.___ of the ocean's area, contains ___ of all marine species and most fisheries

<10% and 90%

4 large areas of global ocean

Atlantic, Arctic, Indian, and Pacific Oceans. The Pacific is the largest; contains more than half of the earth's water and covers one-third of the earth's surface.

Coriolis effect

Because the Earth rotates on its axis, circulating air is deflected right/clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere. This deflection is called the Coriolis effect and also impacts ocean currents.

cold grassland

Cold (e.g. cold grasslands or arctic tundra): Cold grasslands, or arctic tundra, are bitterly cold, treeless plains.

_____ in the atmosphere creates weather and climate

energy

cold forest graph

Cold: northern coniferous (cone-bearing) and boreal. Winters are long and extremely cold. Plant diversity is low, decomposition is slow.

An influencing factor for winds and ocean currents:

Coriolis effect

forest

Cover about 2% of the earth's land surface but are estimated to contain at least 50% of the earth's known terrestrial plant and animal species

Biomes precipitations

Deserts (<25 cm precip.) Grassland (25-75 cm precip.) Shrublands fit here Forests (>75 cm precip.)

3 main types of Deserts

Deserts have low annual precipitation often scattered unevenly throughout the year. The sun warms the ground during the day and evaporates water; heat is quickly lost at night. - Tropical deserts are hot and dry most of the year, with few plants. -Temperate deserts have high daytime temperatures in summer and low in winter. Sparse vegetation is mostly cacti and other succulents. -Cold deserts have sparse vegetation, cold summers and precipitation is low. Desert soils take from decades to centuries to recover from disturbances such as off-road vehicle travel because deserts have slow plant growth, low species diversity, slow nutrient cycling, and very little water.

3 big ideas

Differences in climate, based mostly on long-term differences in average temperature and precipitation, largely determine the types and locations of the earth's biomes: deserts, grasslands, and forests. Saltwater and freshwater aquatic systems cover almost three-fourths of the earth's surface, and oceans dominate the planet. The earth's terrestrial and aquatic systems provide important ecological and economic services, which are being degraded and disrupted by human activities.

Human Impacts on Freshwater Systems

Diversion: Dams and canals Flood control: levees and dikes Wetland and other habitat destruction Pollutants from cities and industry (including thermal pollution) Agricultural pollution leading to eutrophication Overuse: recreation, fishing, building, waste disposal

Mountains important role is..

Diversity: Mountains are steep or high-elevation lands where dramatic changes in altitude, slope, climate, soil, and vegetation take place over a very short distance. Various BIOMES. More on this later... About 1.2 billion people live in mountain ranges or their foothills (17% of the world's population). 4 billion people (57% of the world's population) depend on mountain systems for all or some of their water. Snow = water storage. Many mountains are islands of biodiversity: -sanctuary from people -endemic species -trees

El Nino

El Niño-Southern Oscillation, or ENSO—is an example of the interaction of land and air. Large-scale weather phenomenon occurring every few years when prevailing winds in the tropical Pacific Ocean weaken and change (not known why they do!) ocean current direction. Above-average warming of Pacific waters can affect populations of marine species by changing the distribution of plant nutrients.

energy

Energy powers the movement of air and water. (Temperature is a measure of energy).

Latitude causes

Global Air Circulation - 6 major "cells" of air circulation globally

Saltwater or Marine life zones:

Oceans and their bays, estuaries, and other coastal systems.

Grasslands

Grasslands occur mostly in the interiors of continents in areas too moist for deserts and too dry for forests. Grasslands are not taken over by shrubs and trees because of seasonal droughts, grazing by large herbivores, and occasional fires.

Human activities that impact climate (Laptop H)

Greenhouse gases in the atmosphere case the Greenhouse Effect which leads to global warming and climate change. The major greenhouse gases are: Water vapor (H2O), Carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), as well as CFC's and HFC's. Microclimates in urban areas- "heat island" more haze, smog, higher temps, lower wind speeds in urban areas bricks, asphalt, and traffic create distinct microclimates

Lake Stratification & Turnover

In the Fall and Spring, changing water temperatures can lead to mixing, or "turnover" of water, oxygen, and nutrients.

marin abiotic factors

Key factors determining the type and number of organisms at various depths include: Water temperature and density. Dissolved oxygen content. Availability of food. Availability of light and nutrients required for photosynthesis.

Freshwater life zones

Lakes, rivers, streams, and inland wetlands.

Major factors determining climate

Latitude, Altitude, Prevailing winds, Topography, Ocean currents, Proximity to water

The earth has many different climates

Latitudes Due to the earth's tilt and shape, different Latitudes receive the sun's rays at different angles and intensities. This creates bands of temperature (amongst other things)

El Nino caused

Offshore surface winds weaken. Currents change direction and upwelling of cold, deep, nutrient-rich water weakens. Surface waters warm off of South America Decrease in nutrients reduces primary productivity If pattern lasts 1 year or longer, it can disrupt plankton, fish and seabirds in upwelling areas and trigger extreme weather changes over much of the globe. Consequences of major El Niños: CA- huge waves, torrential rains, flooding & mudslides (1998) Peru - floods & mudslides : hundreds dead, 1/4 million homeless (1998) Drought Brazil, Indonesia & Australia = wildfires Fewer hurricanes in S.E. USA

Precipitation

Precipitation determines whether area is desert/ grassland/ forest. More water (within range) = more life.

Prevailing winds

Prevailing winds blowing over the oceans (Proximity to water) produce mass movements of surface water called Ocean currents. Major ocean currents and upwelling redistribute heat from the sun, influencing climate and vegetation, especially near coastal areas.

3 major types of forest

Temperate, cold, tropical

temperate forest

Temperate: Cool temperatures slow decomposition, so have a thick layer of slowly decaying leaf litter which is a storehouse of nutrients

Altitude

The troposphere (lowest level of atmosphere) is colder at higher elevations due to air expanding and cooling. Helps create BIOMES (more on that later).

Tropical grassland climate

Tropical (e.g. savanna): Savanna contains widely scattered clumps of trees and is usually warm year-round with alternating dry and wet seasons

Three main types of grasslands

Tropical, temperate and cold

Tropical forest graph

Tropical: Found near the equator with a warm and wet climate; ideal for a wide variety of plants and animals. Dominated by broadleaf evergreen plants keep most of their leaves year-round. There is little vegetation on the forest floor because the dense tree-top canopy blocks most light from reaching the ground. Very high net primary productivity and an incredible high level of biological diversity.

Major green house gases

Water vapor (H2O), Carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), as well as CFC's and HFC's.

Benthos

are bottom dwellers. Examples include: Oysters, which anchor themselves to one spot. Clams and some worms, which burrow into the bottom. Lobsters and crabs, which walk on the sea floor.

Tropical deserts

are hot and dry most of the year, with few plants.

Nekton

are strong-swimming consumers such as fish, turtles, and whales found in the pelagic zone.

Aquatic life zones

are the aquatic counterparts of biomes Two major aquatic zones determined by salinity Fresh water and saltwater or marine life

Plankton

are weakly swimming and free-floating. Types include: Phytoplankton: photosynthesizers, includes many types of algae. Zooplankton: plankton that feed on other plankton. Ultraplankton: huge populations of photosynthetic bacteria.

Climate

average weather (temperature & precipitation) over long term (at least 30 yrs)

marine life zones

costal zone, 1. Shallow - high tide mark to edge of continental shelf 2. warm 3. Nutrient rich 4. High primary productivity

Temperature

determines type of desert/ grassland/ forest. More stable temp (within range) = more life.

CLIMATOGRAMS

graph average monthly temperatures with a line and average monthly precipitation with a bar graph. (LAPTOP determines biomes and climate)

Temperate deserts

have high daytime temperatures in summer and low in winter. Sparse vegetation is mostly cacti and other succulents.

cold desert

have sparse vegetation, cold summers and precipitation is low.

coral reefs

importance: 1. Support 25% of all marine species 2. Protect 15% coastline from erosion (reduce wave energy) 3. Cycle carbon - require CO2 for shell formation 4. Produce chemicals useful for medical research Threats: 1. over fishing 2. coral bleaching - Suspended sediment caused by erosion of soil on land smothers polyps, blocks sunlight & kills symbiotic algae. Coral dies & turns white 3. ocean warming= ocean acidification 4. oil spills

lake with low nutrients

oligotrophic

4 main types of aquatic organism

plankton, nekton, Benthos, Decomposers

A watershed

watershed, or drainage basin, is the land area that delivers runoff, sediment, and dissolved substances to a stream or lake. Water flows through 3 distinct